Murray showed courage and resolve many people thought he was incapable of to fight off a stirring Novak Djokovic comeback and seal a five-set US Open triumph.

In doing so, the 25-year-old became the first British tennis player since Fred Perry 76 years ago to win a major and he was cheered on by Ferguson who was present at New York’s Arthur Ashe stadium to witness his semifinal and final victories.

And the 70-year-old was effusive in his praise for his compatriot, who he has taken to following over the years.

Ferguson told BBC Sport: "I'm really proud for the boy. That was a real test of a champion for me. I love watching tennis.”

The Manchester United boss has enjoyed unparalleled success with the Old Trafford side since taking over in 1986, winning 12 Premier League titles and two Champions League trophies, but concedes he was more nervous watching Murray at Flushing Meadows than sitting in the United dugout.

“It was more nerve-wracking than a Premier League match," he admitted. "I'm usually in control of my own situation but I wasn't in control tonight."